Monitoring of micro-drill wear by using the machine vision system

초록

Micro-drill wear deteriorates accuracy and productivity of the micro components. In order to improve productivity and quality of micro components, it is required to investigate micro-drill wear exactly. In this paper, a machine vision system is proposed to measure the wear of micro-drills using a precision servo stage. Calibration experiments are conducted to compensate the machine vision system. Worn volume, area and length are defined as wear amounts. Micro-drill wear is reconstructed as the 3D topography and the quantized wear amount by using the shape from focus (SFF) method and topographic parameters. Experiments have been conducted with HSS twist micro-drills and 0.45% medium-carbon steel workpieces. Validity of the proposed machine vision system is confirmed through experiments.